From the prior art a number of methods are known to disperse or sprinkle particles onto surfaces. From document WO 05/042644 for example a scatter device is known, by means of which the surface of a flooring panel can be sprinkled with abrasion-resistant particles. The abrasion-resistant particles consist for example of corundum or silicon compounds and are sprinkled onto the still wet decor paper of a known laminate panel. After curing of the decor paper under pressure and heat a very resistant surface is formed. The scatter device comprises two rollers, a steel roller as well as a brush roller, which are arranged parallel to each other. The steel roller is provided with small pockets or dimples on its surface and arranged rotatable. Above the steel roller a container is arranged to hold the corundum particles and which dispenses these particles onto the rotating surface of the steel roller in a controlled manner. The dispersed corundum particles collect in the dimples or pockets of the steel roller and are doctored off due to the rotating of the roller and are conveyed further. The brush roller is likewise arranged rotatable and arranged parallel to the side next to the steel roller so that the brush elements can brush out the filled dimples or pockets at the surface of the steel roller. Thereby, the particles which have collected in the dimples or pockets fall down and onto the laminate panels or impregnates which are passed underneath the rollers. The device comprises further conveying equipment by means of which the panels or laminates can be passed in a controlled speed underneath the rollers. The term “impregnate” is widely used in the industry and denotes papers impregnated with resin, as for example the above-mentioned decor papers. These papers serve for example as part of or intermediate product during the manufacturing of laminates.
Although the device work satisfactorily there is still room for improvement. For one it is desirable to improve the control of the dosing of the amount of dispersed particles per time unit along the width. Further, the uniformity of the dispersion of the particles onto the surface can be further improved. A big disadvantage of the above-mentioned device is further, that during the brushing out of the abrasion-resistant particles from the surface respectively out of the pockets in the steel roller, the same is subjected to wear, since the abrasion-resistant particles are considerably tougher than the steel of the steel roller. For this reason, the steel rollers of the prior art have to be exchanged regularly approximately every sixth months in an uninterrupted operation. Thereby costs occur, and the quality of the dispersion at the end of the service time of the steel roller deteriorates.
The above described device is intended to sprinkle the surface of laminate panels or impregnates and similar. Laminate panels usually consist of a four to eight millimeter thick carrier board made from MDF or HDF, onto which upper side a so called decor paper, i.e. a paper printed with a décor and impregnated with a resin, is applied under the application of pressure and heat.
On the bottom side of the carrier board a counter acting paper impregnated with resin is arranged, which serves to counteract a distortion of the carrier board by the applied decor paper. Onto the decor paper an abrasion-resistant layer comprising small corundum particles (which are embedded in a resin matrix), have to be applied, to provide the surface with the necessary durability.
It is the object starting from this prior art to provide a device to disperse particles onto a surface, which eliminates respectively reduces the above-mentioned disadvantages of the prior art. It is in particular an object to provide a device, which allows a well controlled dispersion and which is subjected to a lower amount of wear and can thus be run more cost efficient. It is in particular the object of the invention to provide a device to disperse abrasion resistant particles onto the surface of panels made from wood materials, in particular of laminate panels, as described above.
These and other objects, which will become apparent upon reading the following description or which the skilled person will recognize, are solved by a device according to claim 1 and a method according to claim 15.